The present invention relates generally to electronically controlled automotive air conditioners, and in particular to an automotive air conditioner having a variable capacity compressor, a plurality of evaporators and a plurality of refrigerant flow regulators for independently controlling the temperatures of a plurality of areas within a vehicle passenger compartment in response to thermal loads of the compartment areas.
It is known in the art to independently control a plurality of areas of a vehicle compartment. One prior art system is known as a dual air conditioner having two air distribution conduits, or subsystems, one at the front of the vehicle compartment and the other at the rear thereof and each exhaust duct includes an evaporator therein.
While the front distribution subsystem is designed as a main part of the conditioner, the rear distribution subsystem is usually provided as an optional item to the vehicle owner and installed as an auxiliary part of the conditioner. The evaporator of the front distribution subsystem is directly coupled with the source of refrigerant, whereas the evaporator of the rear subsystem is coupled through an electromagnetically controlled regulating valve. This prevents the refrigerant from being supplied exclusively to the rear-side evaporator and difficulties occur in controlling the individual flow rates when there is a difference in thermal load between the front and rear subsystems.